1. Field of the Invention
This invention relates to a foam rubber composition and a molded product of foam rubber. More particularly, it relates to a foam rubber composition which contains an ethylenepropylene-5-ethylidene-2-norbornene copolymer (hereinafter referred to as "ENB type EPDM") as its rubber component, maintains an outstanding level of workability, is formable to a high degree, and has a high rigidity, a low compression set and a high shape-retaining property, and to a molded product made of this foam rubber composition.
2. Description of Related Art
An ENB type EPDM is widely used for making automobile parts owing to its outstanding properties including weather, heat and ozone resistance. The ENB type EPDM is an ethylenepropylene-unconjugated diene terpolymer containing 5-ethylidene-2-norbornene as its unconjugated diene. The applicable automobile parts include at weather strip W1 (see FIG. 1) and a hose protector which are made by foaming a rubber copolymer and molding it. The sponge rubber which is used for such purposes is required to have a high rigidity, a low compression set and a high shape-retaining property for maintaining a high sealing property for a long period of time, while from the standpoint of cost reduction, etc., it is required to be formable to a high degree. These requirements have recently become increasingly more stringent. However, no conventional rubber has been found that is satisfactory for maintaining an outstanding level of workability, formable to a high degree, having a high rigidity, a low compression set and a high shape-retaining property.